4" exhaust rules
Hotshot
Joined: Jan 2011
Posts: 18,849
Likes: 179
From: Puget Sound
4" does make a difference in boost. I explained why here https://www.ford-trucks.com/forums/1...l#post11589373
Like Nicmike, I notice the power difference in the lower RPM band. I have better passing acceleration above 55 if I don't punch it hard enough to drop out of OD. I drove uphill through a tunnel at 40 MPH with the windows down and punched it. My testost-o-meter pegged out and nearby small woodland creatures flat died from heart failure as my wife rolled her eyes - hair flopping wildly about.
I tried getting a recording of the sound by wearing a GoPro on my head, but the audio didn't work the way I planned. Meanwhile, my wife is watching me stomp on a diesel - in a tunnel - with the windows down - and a camera on a headband, as she says "Stand back girls. I saw him first!"
Like Nicmike, I notice the power difference in the lower RPM band. I have better passing acceleration above 55 if I don't punch it hard enough to drop out of OD. I drove uphill through a tunnel at 40 MPH with the windows down and punched it. My testost-o-meter pegged out and nearby small woodland creatures flat died from heart failure as my wife rolled her eyes - hair flopping wildly about.
I tried getting a recording of the sound by wearing a GoPro on my head, but the audio didn't work the way I planned. Meanwhile, my wife is watching me stomp on a diesel - in a tunnel - with the windows down - and a camera on a headband, as she says "Stand back girls. I saw him first!"
Mountain Pass
Joined: May 2005
Posts: 180
Likes: 0
4" does make a difference in boost. I explained why here https://www.ford-trucks.com/forums/1...l#post11589373
Like Nicmike, I notice the power difference in the lower RPM band. I have better passing acceleration above 55 if I don't punch it hard enough to drop out of OD. I drove uphill through a tunnel at 40 MPH with the windows down and punched it. My testost-o-meter pegged out and nearby small woodland creatures flat died from heart failure as my wife rolled her eyes - hair flopping wildly about.
I tried getting a recording of the sound by wearing a GoPro on my head, but the audio didn't work the way I planned. Meanwhile, my wife is watching me stomp on a diesel - in a tunnel - with the windows down - and a camera on a headband, as she says "Stand back girls. I saw him first!"
Like Nicmike, I notice the power difference in the lower RPM band. I have better passing acceleration above 55 if I don't punch it hard enough to drop out of OD. I drove uphill through a tunnel at 40 MPH with the windows down and punched it. My testost-o-meter pegged out and nearby small woodland creatures flat died from heart failure as my wife rolled her eyes - hair flopping wildly about.
I tried getting a recording of the sound by wearing a GoPro on my head, but the audio didn't work the way I planned. Meanwhile, my wife is watching me stomp on a diesel - in a tunnel - with the windows down - and a camera on a headband, as she says "Stand back girls. I saw him first!"
That's what I'm talkin about!!! Ha Ha!!
Veteran/Sheepdog
Joined: Feb 2012
Posts: 6,047
Likes: 110
From: Western AR
LOL! Good stuff, Tugly. The ONLY reason I got the 5" exhaust was I found it and a 4" downpipe for $75 at a junkyard while pulling a rear swaybar off a F350. I didn't want one bad enough to pay retail for it! The junkyard didn't know what they had or what it was worth...
For all the argument in the other thread, I can just say my truck runs MUCH BETTER with the 5" than it did with the stock setup.
Mike
For all the argument in the other thread, I can just say my truck runs MUCH BETTER with the 5" than it did with the stock setup.
Mike
Junior User
Joined: Mar 2012
Posts: 73
Likes: 0
From: Spokane, WA
Lucky! I got everything lined up yesterday and all the tools gathered to put mine on and then I discovered they forgot to give me the hanger clamp. I was just glad I figured it out before I took the stock exhaust off the truck.
Laughing Gas
Joined: Aug 2010
Posts: 1,098
Likes: 6
From: Ventura co.
Mine did the same as you. But i put the DP tuner in when i did the exhaust.
I posted a trip that i did. I got 18.8 on the flat road, then 14.9 climbing the cajon pass then 17.9 to dumont. my over all mileage turned out to be 16.8 mpg on my 580 mile trip. before the exhaust and tuner i was getting around 12.8 to 14.5
This was done by filling the truck to the neck and refilling divided by mileage at three stops and refilling when i got home
I posted a trip that i did. I got 18.8 on the flat road, then 14.9 climbing the cajon pass then 17.9 to dumont. my over all mileage turned out to be 16.8 mpg on my 580 mile trip. before the exhaust and tuner i was getting around 12.8 to 14.5
This was done by filling the truck to the neck and refilling divided by mileage at three stops and refilling when i got home
Logistics Pro
Joined: Dec 2010
Posts: 4,738
Likes: 15
From: Temperance, MI
4" does make a difference in boost. I explained why here https://www.ford-trucks.com/forums/1...l#post11589373
Like Nicmike, I notice the power difference in the lower RPM band. I have better passing acceleration above 55 if I don't punch it hard enough to drop out of OD. I drove uphill through a tunnel at 40 MPH with the windows down and punched it. My testost-o-meter pegged out and nearby small woodland creatures flat died from heart failure as my wife rolled her eyes - hair flopping wildly about.
I tried getting a recording of the sound by wearing a GoPro on my head, but the audio didn't work the way I planned. Meanwhile, my wife is watching me stomp on a diesel - in a tunnel - with the windows down - and a camera on a headband, as she says "Stand back girls. I saw him first!"
Like Nicmike, I notice the power difference in the lower RPM band. I have better passing acceleration above 55 if I don't punch it hard enough to drop out of OD. I drove uphill through a tunnel at 40 MPH with the windows down and punched it. My testost-o-meter pegged out and nearby small woodland creatures flat died from heart failure as my wife rolled her eyes - hair flopping wildly about.
I tried getting a recording of the sound by wearing a GoPro on my head, but the audio didn't work the way I planned. Meanwhile, my wife is watching me stomp on a diesel - in a tunnel - with the windows down - and a camera on a headband, as she says "Stand back girls. I saw him first!"
That sounds like my wife, I jumped a set of tracks on accident awhile back and caught about 2 feet of air, it was a strange road and it was rough so.... I go faster so the truck rides smoother, I hit the tracks went in the air, landed as smooth as could be and my wife was just as excited as I was.
Hotshot
Joined: Jan 2011
Posts: 18,849
Likes: 179
From: Puget Sound
Jumping tracks? I'll just bet if you tried that again, she just might imply she's done with that.
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Postmaster
Joined: Jul 2006
Posts: 4,993
Likes: 2
From: Bend, OR
UGH... Really? Please install a pressure gauge in your exhaust system and tell me at what point you have ANY PRESSURE READING WHAT SO EVER...
Now install one on the exhaust side of your turbo... at 27psi you will see about 40-45psi drive pressure...
Now install one on the exhaust side of your turbo... at 27psi you will see about 40-45psi drive pressure...
Hotshot
Joined: Jan 2011
Posts: 18,849
Likes: 179
From: Puget Sound
Here is the 4".
Postmaster
Joined: Jul 2006
Posts: 4,993
Likes: 2
From: Bend, OR
You do understand what exhaust back pressure is correct? It is not what is past the turbo, but what is in the EXHAUST MANIFOLDS...
How can you not understand that...
Your second doesnt even have boost levels on it, or it is labled wrong.
How can you not understand that...
Your second doesnt even have boost levels on it, or it is labled wrong.
Hotshot
Joined: Jan 2011
Posts: 18,849
Likes: 179
From: Puget Sound
I fixed the attachment - my bad. I don't trust my MAP, I'm reporting boost from the gauge.
The point of those two graphs:
Going to the 4" exhaust reduces/eliminates this back pressure downstream from the turbo and the pressure differential is greater, forcing the turbo to spool up rapidly.
OR
Everybody (including myself) is full of carp when we state we notice a difference with the 4".
Is there a third way of looking at this?
The point of those two graphs:
- I see no change in EBP before/after 4" during WOT acceleration on any of my graphing.
- My boost behaves differently - instead of immediate 20 PSI and climb to 27 PSI with RPM, I now see an immediate 27 PSI boost.
- I "feel" more acceleration at lower RPMs (I'm assuming more torque).
- Many others report the same experience when going to 4" exhaust.
Going to the 4" exhaust reduces/eliminates this back pressure downstream from the turbo and the pressure differential is greater, forcing the turbo to spool up rapidly.
OR
Everybody (including myself) is full of carp when we state we notice a difference with the 4".
Is there a third way of looking at this?
Postmaster
Joined: Jul 2006
Posts: 4,993
Likes: 2
From: Bend, OR
I fixed the attachment - my bad. I don't trust my MAP, I'm reporting boost from the gauge.
The point of those two graphs:
Going to the 4" exhaust reduces/eliminates this back pressure downstream from the turbo and the pressure differential is greater, forcing the turbo to spool up rapidly.
OR
Everybody (including myself) is full of carp when we state we notice a difference with the 4".
Is there a third way of looking at this?
The point of those two graphs:
- I see no change in EBP before/after 4" during WOT acceleration on any of my graphing.
- My boost behaves differently - instead of immediate 20 PSI and climb to 27 PSI with RPM, I now see an immediate 27 PSI boost.
- I "feel" more acceleration at lower RPMs (I'm assuming more torque).
- Many others report the same experience when going to 4" exhaust.
Going to the 4" exhaust reduces/eliminates this back pressure downstream from the turbo and the pressure differential is greater, forcing the turbo to spool up rapidly.
OR
Everybody (including myself) is full of carp when we state we notice a difference with the 4".
Is there a third way of looking at this?
HOWEVER what everyone is telling you is there is no REASON to go larger then a 4" system.
If there was 5psi of back pressure in the exhaust system then you could argue your point, however there is not. You have 55psi coming from the turbine housing that drops to 0 once past the outlet of the turbo.
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